1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>usb_gadget_get_string</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="USB Gadget API for Linux"><link rel="up" href="utils.html" title="Optional Utilities"><link rel="prev" href="utils.html" title="Optional Utilities"><link rel="next" href="API-usb-descriptor-fillbuf.html" title="usb_descriptor_fillbuf"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">usb_gadget_get_string</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="utils.html">Prev</a>&#160;</td><th width="60%" align="center">Optional Utilities</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-usb-descriptor-fillbuf.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-usb-gadget-get-string"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>usb_gadget_get_string &#8212; 
2  fill out a string descriptor
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">usb_gadget_get_string </b>(</code></td><td>struct usb_gadget_strings * <var class="pdparam">table</var>, </td></tr><tr><td>&#160;</td><td>int <var class="pdparam">id</var>, </td></tr><tr><td>&#160;</td><td>u8 * <var class="pdparam">buf</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1124244844"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>table</code></em></span></dt><dd><p>
4     of c strings encoded using UTF-8
5    </p></dd><dt><span class="term"><em class="parameter"><code>id</code></em></span></dt><dd><p>
6     string id, from low byte of wValue in get string descriptor
7    </p></dd><dt><span class="term"><em class="parameter"><code>buf</code></em></span></dt><dd><p>
8     at least 256 bytes, must be 16-bit aligned
9    </p></dd></dl></div></div><div class="refsect1"><a name="idp1124248468"></a><h2>Description</h2><p>
10   Finds the UTF-8 string matching the ID, and converts it into a
11   string descriptor in utf16-le.
12   Returns length of descriptor (always even) or negative errno
13   </p><p>
14
15   If your driver needs stings in multiple languages, you'll probably
16   <span class="quote">&#8220;<span class="quote">switch (wIndex) { ... }</span>&#8221;</span>  in your ep0 string descriptor logic,
17   using this routine after choosing which set of UTF-8 strings to use.
18   Note that US-ASCII is a strict subset of UTF-8; any string bytes with
19   the eighth bit set will be multibyte UTF-8 characters, not ISO-8859/1
20   characters (which are also widely used in C strings).
21</p></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="utils.html">Prev</a>&#160;</td><td width="20%" align="center"><a accesskey="u" href="utils.html">Up</a></td><td width="40%" align="right">&#160;<a accesskey="n" href="API-usb-descriptor-fillbuf.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Optional Utilities&#160;</td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top">&#160;<span class="phrase">usb_descriptor_fillbuf</span></td></tr></table></div></body></html>
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